Telecommunications systems use a variety of communications protocols and protocol variations to provide telephony services. For example, integrated services digital network (ISDN) communications may rely on any number of different ISDN protocol variations to establish ISDN calls or other connections and process ISDN signaling events associated with those connections. A telephony switch or other telecommunications system may be configured to support one or more ISDN protocol variations using an ISDN protocol stack. The ISDN protocol stack may contain information for establishing ISDN connections and processing associated ISDN signaling events using any ISDN protocol variation for which the protocol stack is configured. At times it may be necessary or desirable to upgrade, replace, or otherwise modify certain functionality within an ISDN or other communications protocol stack, for example, because of a modification of the defining specification of a particular protocol variation or because a problem has been found with the current implementation. As these modifications are performed in previous systems, the quality of service provided to network users may be compromised.